Ventilating fans



Jan. 7, 1964 T. SOLEM VENTILATING FANS Filed Dec. 11, 1961 .Iilll'r f /vVEN ToK United States Patent 3,116,679 VENTHJATING FANS Thorolf Solem,Stangebrua, Hamm, Norway Filed Dec. 11, 1961, Ser- No. 158,307 3 Claims.(Cl. 98-416) The present invention relates to improvements inventilating fans.

An object of the invention is to provide a ventilating fan having acompact construction, which does not restrict the free air passage, andwith details which can be simply and cheaply fabricated retaining thenecessary strength and durability.

According to the present invention there is provided a ventilation fancomprising an open-ended housing, a motor mounted therein for drivingthe blades of the fan, a cover mounted on one end of the housing formovement in a predetermined direction between a first position in whichthe cover leaves the housing end open, and a second closing position,spring means urging the cover into the second position against said end,first cam means mounted on the motor for rotation about an axis parallelto the direction of cover movement, and second cam means secured to thecover and cooperating with said first cam means. Respective cam faces ofthe first and second cam means which are obliquely inclined relative tothe axis are in conforming engagement with each other under the urgingof the spring means. The faces extends in respective circular arcs aboutthe axis, whereby the cover is moved from the second to the firstposition when the first cam means rotate about the axis.

For a better understanding of the present invention, and to show how thesame may be carried into effect, reference 'will now be made, by way ofexample, to the accompanying drawing, in which:

FIGURE 1 is a vertical section through the axis of a ventilating fan,and

FIGURE 2 is a section along the line II-II in FIG- URE 1.

An open-ended housing 1 is inserted into a ventilation channel in a Walland has at one end a peripheral flange 2 which abuts the Wall and issecured thereto. Radial arms 3 secure a motor 4, which drives fan blades5, centrally within the housing 1. Between the motor 4 and a cover 6,which shields the inlet opening of the housing 1, a rotatable sleeve 7is positioned co-axial with the motor. The sleeve 7 has a circular rib 7which rotatably engages in a corresponding groove formed in the adjacentend part 4' of the motor housing. Radial arms 8 fix an outer ring 9 tothe sleeve 7, the ring 9 being housed in an annular groove it} in theflange 2.

A pair of guiding rods 11, parallel to the axis of the motor 4, aresupported by, and axially displaceable through bores in, the arms 3. Oneend of each rod 11 projects from the housing 1 to support the cover 6while the other end of each rod 11 extends in the other direction beyondthe arms 3. On these other ends are mounted helical springs 12 which actthrough pins passed through the rods 11 to urge the rods 11 into thehousing 1.

A number of cam pieces 13 are secured to the inner surface of the sleeve7 and are evenly distributed around said inner surface. Each cam piece13 has a cam surface 13' which co-operates with a cam surface 14' ofcorresponding cam pieces 14 which project from the inside of the cover6. The cam pieces 14 are arranged so that they can penetrate the sleeve7 with the cam profiles 14' engaging the cam profiles 13.

The sleeve 7 is rotated by means of a line 15 the ends of which aresecured to the ring 9. The pitch of the cam surfaces 13', 14 is sochosen that by rotating the sleeve approximately a quarter of arevolution the cover Patented Jan. 7, 1954- 6 is moved from a fullyopened position to a closed position where the cover 6 is pressedagainst the flange 2 by the springs 12. During this movement the rods 11pass freely between two adjacent arms 8.

A clockwise rotation of the sleeve 7, and thus the cam surfaces 13, fromthe position shown in FIGURE 2, allows the cam pieces 14 to penetratethe sleeve 7 under the action of the springs 12. The rotation can becontinued until the cover 6 bears against the flange 2.

By rotating the sleeve 7 in the opposite direction the cam surfaces 13acting on the cam surfaces 14 force the guiding rods 11 against theaction of the springs 12 and thereby move the cover 6 outwardly untilthe cover reaches the fully opened position.

The current to the motor 4 is controlled by a tumbler switch 16 thetumbling arm 17 of which projects between two radial arms 8. These twoarms 3 co-operate with the arm 17 to switch the current on and off inthe fully open and closed position respectively of the cover 6.

The springs 12 exert axial forces on the guiding rods 11 which actthrough the cover 6, cam pieces .13, 14 and sleeve 7, and hold the rib'7' engaged in the circular groove in the end part 4'.

In the embodiment shown and described, the cams 'formoving the cover 6do not project outside a prolongation of the circumference of the motorand consequently the free air passage is not restricted.

What I claim is:

1. A ventilating fan comprising in combination, a housing having twoopen ends, a fan driving motor in said housing, a housing cover, meansfor fixedly mounting said motor in said housing and for mounting thecover on the housing for movement of the cover toward and away from oneof said open ends of the housing, said mounting means including aplurality of arm members extending between said housing and said motorin respective angularly spaced radial directions, a plurality of guidingrods, means for slidably mounting said guiding rods on respective onesof said arm members for movement toward and away from said one of saidopen ends, said housing cover being fastened to said guiding rods,spring means including a plurality of coil springs mounted on saidguiding rods and connected to said housing and to said cover for urgingthe cover toward said one of said open ends of the housing, a first cammember and a second cam member, means rotatably securing said first cammember to said motor for rotation about an axis of said housing passingthrough said open ends, means fixedly securing said second cam member tosaid cover, said first and second cam members each having a plurality ofcam faces obliquely inclined relative to said axis and extending inrespective circular arcs about said axis, the cam faces of each cammember conformingly engaging the cam faces of the other cam member, andmeans for rotating said first cam member.

2. The device as defined in claim 1 wherein said last mentioned meansinclude a sleeve member fixedly fastened to said first cam member, andmeans for rotating said sleeve member about said axis.

3. The device as defined in claim 1 together with switch meansresponsive to rotation of said first cam member for controlling saidmotor.

References Cited in the file of this patent UNITED STATES PATENTS1,890,758 Townsend Dec. 13, 1932 FOREIGN PATENTS 84,361 Norway Aug. 7,1954 108,911 Sweden Nov. 2, 1943 152,665 Sweden Dec. 13, 1955

1. A VENTILATING FAN COMPRISING IN COMBINATION, A HOUSING HAVING TWOOPEN ENDS, A FAN DRIVING MOTOR IN SAID HOUSING, A HOUSING COVER, MEANSFOR FIXEDLY MOUNTING SAID MOTOR IN SAID HOUSING AND FOR MOUNTING THECOVER ON THE HOUSING FOR MOVEMENT OF THE COVER TOWARD AND AWAY FROM ONEOF SAID OPEN ENDS OF THE HOUSING, SAID MOUNTING MEANS INCLUDING APLURALITY OF ARM MEMBERS EXTENDING BETWEEN SAID HOUSING AND SAID MOTORIN RESPECTIVE ANGULARLY SPACED RADIAL DIRECTIONS, A PLURALITY OF GUIDINGRODS, MEANS FOR SLIDABLY MOUNTING SAID GUIDING RODS ON RESPECTIVE ONESOF SAID ARM MEMBERS FOR MOVEMENT TOWARD AND AWAY FROM SAID ONE OF SAIDOPEN ENDS, SAID HOUSING COVER BEING FASTENED TO SAID GUIDING RODS,SPRING MEANS INCLUDING A PLURALITY OF COIL SPRINGS MOUNTED ON SAIDGUIDING RODS AND CONNECTED TO SAID HOUSING AND TO SAID COVER FOR URGINGTHE COVER TOWARD SAID ONE OF SAID OPEN ENDS OF THE HOUSING, A FIRST CAMMEMBER AND A SECOND CAM MEMBER, MEANS ROTATABLY SECURING SAID FIRST CAMMEMBER TO SAID MOTOR FOR ROTATION ABOUT AN AXIS OF SAID HOUSING PASSINGTHROUGH SAID OPEN ENDS, MEANS FIXEDLY SECURING SAID SECOND CAM MEMBER TOSAID COVER, SAID FIRST AND SECOND CAM MEMBERS EACH HAVING A PLURALITY OFCAM FACES OBLIQUELY INCLINED RELATIVE TO SAID AXIS AND EXTENDING INRESPECTIVE CIRCULAR ARCS ABOUT SAID AXIS, THE CAM FACES OF EACH CAMMEMBER CONFORMINGLY ENGAGING THE CAM FACES OF THE OTHER CAM MEMBER, ANDMEANS FOR ROTATING SAID FIRST CAM MEMBER.